Attachment structure of blower

ABSTRACT

A blower is attached to a heat exchanger through an attachment member. One of the heat exchanger and the attachment member has at least one engagement portion which is detachably engaged by an elastic deformation with a hole portion provided in other one of the heat exchanger and the attachment member. At least one of the heat exchanger and the attachment member is deformed before the engagement portion is engaged with the hole portion, and is deflected and reformed when the engagement portion engages with the hole portion. Accordingly, a counteractive force due to a deflection is applied to the attachment member, to be pressed to the heat exchanger. Therefore, a relative movement between the attachment member and the heat exchanger can be restricted, even if a gap is formed therebetween when the attachment member is attached to the heat exchanger.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Application No. 2003-363476filed on Oct. 23, 2003, the disclosure of which is incorporated hereinby reference.

FIELD OF THE INVENTION

The present invention relates to an attachment structure for attaching ablower to a heat exchanger. The blower is provided to blow air to theheat exchanger, for example, a radiator in a vehicle.

BACKGROUND OF THE INVENTION

Generally, a blower is attached to a radiator of a vehicle through anattachment member such as a shroud. Protruding portions provided in theradiator are inserted into U-shape grooves provided in the shroud atlower attachment positions of the shroud, so that the shroud is attachedto the radiator (for example, refer to JP-A-11-229878). The shroud isfixed to the radiator (i.e., heat exchanger) by using bolts at two upperattachment positions.

The shroud is disposed to shroud a gap between the blower and theradiator, thereby restricting an air flow induced by the blower frombypassing the radiator. Therefore, a cooling capacity of the radiatorcan be increased.

However, in the attachment structure referring to JP-A-11-229878,fastening members such as the bolts and nuts are necessary in additionto the radiator, the blower and the shroud. As a result, it takes longertime for attaching the blower and for classifying the attachmentstructure of the blower when being recycled. Therefore, a recyclingperformance of the attachment structure is deteriorated.

An attachment structure, in which the blower is attached to the radiatorwithout using the bolts or the nuts, is proposed in JP-A-2002-4861. Inthis attachment structure, protruding portions, which protrude from theradiator, fit with recessed portions provided in the shroud, so that avertical load (i.e., self-weight) applied to the blower is received bythe shroud. Furthermore, engagement protruding portions, which protrudefrom the radiator, engage with engagement hole portions provided in theshroud, so that a horizontal load (i.e., exciting force) applied to theblower is received by the shroud. However, in this attachment structure,a gap may be formed between the engagement protruding portion and theengagement hole portion due to a dimension difference of the engagementprotruding portion, when the shroud is attached to the radiator. In thiscase, the shroud may be moved relative to the radiator.

SUMMARY OF THE INVENTION

In view of the above-described problems, it is an object of the presentinvention to provide an attachment structure for attaching a blower to aheat exchanger (e.g. radiator) through an attachment member (e.g.shroud) while a relative movement between the attachment member and theheat exchanger can be restricted.

According to the present invention, an attachment structure includes aheat exchanger for heat-exchanging between air and a fluid therein, ablower for blowing air to the heat exchanger, and an attachment memberthrough which the blower is attached to the heat exchanger. In theattachment structure, one of the heat exchanger and the attachmentmember has at least one engagement portion, and the engagement portionis detachably engaged by an elastic deformation with a hole portionwhich is provided in other one of the heat exchanger and the attachmentmember. In addition, at least one of the heat exchanger and theattachment member is deformed before the engagement portion is engagedwith the hole portion, and is deflected and reformed due to deformationwhen the engagement portion engages with the hole portion.

Alternatively, in an attachment structure of the present invention, theheat exchanger has a fitting surface that is arranged opposite to afitting surface of the attachment member when the engagement portionengages with the hole portion, and one of the fitting surfaces of theheat exchanger and the attachment member is bent to be tilted withrespect to other one of the fitting surfaces before the engagementportion is engaged with the hole portion.

Accordingly, when the attachment member is attached to the heatexchanger, at least one of the attachment member and the heat exchangerhas a deflection, so that a counteractive force is applied to the one ofthe attachment member and the heat exchanger. As a result, the one ofthe attachment member and the heat exchanger is pressed to the other oneof the attachment member and the heat exchanger. Accordingly, even if agap is formed between the engagement portion and the hole portion whenbeing assembled, the attachment member is not removed from the heatexchanger.

Preferably, when the engagement portion engages with the hole portion,at least one of the heat exchanger and the attachment member isdeflected and reformed so that the fitting surfaces of the heatexchanger and the attachment member becomes approximately parallel toeach other.

For example, at least three the engagement portions are arranged in aline in an arrangement direction perpendicular to an air flowingdirection of the heat exchanger, and the one of the fitting surfaces ofthe heat exchanger and the attachment member is bent to have a convexshape at an approximate middle area in the arrangement direction beforethe engagement portion is engaged with the hole portion. The one of thefitting surfaces of the heat exchanger and the attachment member can bebent to have a v-shape or a wave shape before the engagement portion isengaged with the hole portion.

Further, the one of the fitting surfaces of the heat exchanger and theattachment member can be provided on the attachment member. In addition,the engagement portion can be provided in the heat exchanger, and thehole portion can be provided in the attachment member.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention willbecome more apparent from the following detailed description made withreference to the accompanying drawings, in which:

FIG. 1 is a front view showing a radiator and blowers attached to theradiator by using an attachment structure according to a preferredembodiment of the present invention;

FIG. 2A is a cross-sectional view of the attachment structure at a lowerattachment position according to the preferred embodiment, and FIG. 2Bis a partial enlarged sectional view taken along a line IIB-IIB in FIG.2A;

FIG. 3 is a cross-sectional view of the attachment structure at an upperattachment position according to the preferred embodiment;

FIGS. 4A, 4B and 4C are cross-sectional views showing a attachingprocess of the attachment structure at the upper attachment positionaccording to the preferred embodiment;

FIG. 5 is a disassembled cross-sectional view showing characteristics ofthe attachment structure according to the preferred embodiment;

FIG. 6 is a cross-sectional view showing characteristics of theattachment structure according to the preferred embodiment; and

FIG. 7 is a cross-sectional view showing characteristics of anattachment structure in a comparison example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A preferred embodiment of the present invention will be describedreferring to FIGS. 1-6. In this preferred embodiment, an attachmentstructure of the present invention is typically used for attaching ablower 20 to a radiator 10 in a vehicle. FIG. 1 is a front view of theradiator 10 and the blower 20 when viewed from a downstream air side toan upstream air side. In this embodiment, the blower 20 is adrawing-type blower disposed on the downstream air side with respect tothe radiator 10. The blower 20 draws air from the downstream air side ofthe radiator 10, so that air is blown to the radiator 10. Alternatively,the blower 20 can also be a forcing-type blower which is disposed on theupstream air side with respect to the radiator 10. The forcing-typeblower blows air to push an air flow to the radiator 10.

In this embodiment, the radiator 10 is a heat exchanger for radiatingheat to air. The radiator 10 is provided with at least oneheat-exchanging core and header tanks 11. Each of the heat-exchangingcores includes plural tubes (not shown) and plural wave-shape fins (notshown). Engine-cooling water circulates in an internal-combustion engine(i.e., vehicle driving source for traveling) to recover heat from theengine, and flows through the tubes to radiate the heat to air. Theplural fins are disposed between the adjacent tubes for improving theheat exchanging performance between air and the engine-cooling water.The header tanks 11, communicating with each of the tubes, are disposedat two end sides of the tubes in a longitudinal direction of the tubes,and extend in a direction perpendicular to the longitudinal direction ofthe tubes.

In this embodiment, the longitudinal direction of the tubes is arrangedto correspond to a vertical direction of the vehicle. Moreover, alongitudinal direction of the header tank 11 is arranged to correspondto a horizontal direction of the vehicle. The engine-cooling water flowsfrom the upper one of the header tanks 11 to each of the tubes in whichthe engine-cooling water is heat-exchanged, and thereafter is collectedin the lower one of the header tanks 11 from each of the tubes.

The tubes and the fins are made of metal (e.g., aluminum in thisembodiment). Each of the header tanks 11 includes a core plate (notshown) which is made of metal (e.g., aluminum in this embodiment) to bebonded with the tubes by brazing, and a tank body 11 a made of resin.That is, the core plate and the tank body 11 a are connected to form aninner space of the header tank 11. A part of the core plate of theheader tank 11 is plastically deformed to be assembled with the tankbody 11 a using a seal member such as a packing (not shown).

Here, the brazing is a bonding technology where the bonding is performedby using a brazing metal or a solder while a base material is notmelted, as described in, for example, Connection and Junction Technology(Tokyo Electrical Machinery University Publishing Company).

Generally, the brazing is referred when the bonding is performed byusing a metal material with a melting point beyond 450° C., and thismetal material is called as the brazing material. In contrast, asoldering is referred when the bonding is performed by using a metalmaterial with a melting point below 450° C., and this metal material iscalled as the solder.

The blower 20 includes an axis-flow fan 21 for inducing an air flow, andan electric motor 22 for driving and rotating the fan 21.

The fan shroud 30 shrouds a gap between the radiator 10 and the blower20 to define an air passage (i.e., duct for an air flow) therebetween,so that the blower 20 is restricted from drawing air from the downstreamair side with respect to the radiator 10. Accordingly, the air flowinduced by the blower 20 does not bypass the radiator 10.

At least one blower 20 (e.g., two as shown in FIG. 1) is attached to theradiator 10 through the fan shroud 30 which corresponds to an attachmentmember in the present invention. The fan shroud 30 is made of resin(e.g., polypropylene in this embodiment). The motor 22 of each blower 20is fixed to the fan shroud 30 through fastening members such as bolts.

Next, the attachment structure of the blower 20 to the radiator 10, thatis, the attachment structure of the fan shroud 30 to the radiator 10will be now described.

As shown in FIG. 1, the fan shroud 30 is attached to the radiator 10 atfive attachment positions P1-P5. At each of lower attachment positionsP4 and P5, a U-shape groove 31 is provided in the fan shroud 30, and aprotruding portion 11 b is provided in the tank body 11 a of theradiator 10. The protruding portion 11 b is inserted into the U-shapegroove 31 to engage with the U-shape groove 31 as shown in FIGS. 2A and2B. Moreover, an umbrella portion 11 c is provided in a tip portion ofthe protruding portion 11 b, and extends in a direction perpendicular toa protruding direction (i.e., longitudinal direction of vehicle) of theprotruding portion 11 b. That is, the umbrella portion 11 c is anenlarged portion extending in a lateral direction of the vehicle.Therefore, the umbrella portion 11 c restricts the protruding portion 11b from being removed from the U-shape groove 31.

As shown in FIG. 3, at each of upper attachment positions P1-P3, a pairof plate-shape protruding portions 12 (i.e., convex portion) areprovided to protrude from the tank body 11 a and a recessed portion 32is provided in the fan shroud 30. The pair of plate-shape protrudingportions 12 are fitted with the recessed portion 32, and respectivelycontact a left-side surface and a right-side surface of an inner walldefining the recessed portion 32 of the fan shroud 30.

Moreover, at each of the upper attachment positions P1-P3, a flexibleengagement protruding portion 13 is provided to protrude from the tankbody 11 a between the pair of protruding portions 12, and an engagementhole portion 33 is provided in the fan shroud 30 at a bottom of theinner wall defining the recessed portion 32, as shown in FIG. 3. Theplural flexible engagement protruding portions 13 (e.g., three) arearranged approximately in an approximate line with respect to the airflowing direction. Each of the engagement protruding portion 13 engageswith each of the engagement hole portion 33 of the fan shroud 30 at thecorresponding position, while the pair of plate-shaped protrudingportions 12 contact the inner wall surface of the recessed portion 32.That is, the engagement protruding portion 13 of the tank body 11 a ishitched by the engagement hole portion 33 of the fan shroud 30.

An engaging nail portion 13 a is integrally formed with the engagementprotruding portion 13 at a tip portion of the engagement protrudingportion 13, so that a disengaging of the engagement protruding portion13 from the engagement hole portion 33 can be restricted.

In the attachment structure according to this embodiment, the protrudingportion 11 b of the radiator 10 is firstly inserted into the U-shapegroove 31 of the fan shroud 30 at each of the lower attachment positionsP4 and P5 as shown in FIGS. 2A and 2B. Next, at each of the upperattachment positions P1-P3, while the pair of protruding portions 12 arefitted into the recessed portion 32 to contact the inner wall surface ofthe recessed portion 32, the engagement protruding portions 13 areflexibly and elastically deformed to be inserted into the engagementhole portion 33 as shown in FIGS. 4A-4C. Thus, the fan shroud 30detachably engages with the radiator 10.

FIG. 5 shows a disassembled state of the engaged structure between theradiator 10 and the fan shroud 30, and FIG. 6 shows an assembled stateof the engaged structure between the radiator 10 and the fan shroud 30.As shown in FIGS. 5 and 6, at the upper attachment positions P1-P3, afitting surface 11 d of the tank body 11 a is arranged opposite to afitting surface 30 a of the fan shroud 30 when being assembled. In thiscase, it is unnecessary for the fitting surface 11 d to contact thefitting surface 30 a. Moreover, when viewed in a direction perpendicularto the air flowing direction (vehicle front-rear direction), the fittingsurface 30 a is tilted with respect to the fitting surface 11 d as shownin FIGS. 5 and 6. That is, in this embodiment, the fitting surfaces 11 dand 30 a are opposite to each other to be not actually parallel witheach other. Further, it is unnecessary for the fitting surfaces 11 d and30 a to completely overlap, when viewed from the air flowing direction.For example, when viewed from the air flowing direction (front-reardirection), both the fitting surfaces 11 d and 30 a can be offset fromeach other in a direction (face-back direction of paper in FIG. 6)perpendicular to the air flowing direction.

In this embodiment, when the fan shroud 30 is not engaged with theradiator 10, one (i.e., fitting surface 30 a in this embodiment) of thefitting surfaces 11 d and 30 a is beforehand deformed by bending, andthereby offsetting from the other (i.e., fitting surface 11 d in thisembodiment) at two end sides of the arrangement line in which the threeengagement protruding portions 13 are arranged. That is, a slant anglebetween the fitting surface 30 a and the fitting surface 11 d is set at1.5°, for example, in this embodiment. At an approximate middle part ofthe arrangement line, the fitting surface 30 a is beforehand bent toprotrude to the side of the fitting surface 11 d in the air flowingdirection (i.e., vehicle front-rear direction). Therefore, the fittingsurface 30 a has a slight bent shape such as a large-angle V-shape, asshown in FIG. 5.

Therefore, when the engagement protruding portion 13 of the radiator 10engages with the engagement hole portion 33 of the fan shroud 30, thefan shroud 30 is reformed and deflected. That is, as shown in FIG. 6, ateach of the upper attachment positions P1 and P3, a deflecting force isapplied to the fan shroud 30 by the engagement protruding portion 13 sothat the fitting surface 30 a becomes approximately parallel to thefitting surface 11 d. Meanwhile, at a top portion (i.e., at attachmentposition P2) of the fitting surface 30 a having approximately thelarge-angle V-shape, the tank body 11 a applies a force in a contrarydirection to that of the deflecting force to the fan shroud 30. As aresult, the fitting surface 30 a becomes approximately parallel to thefitting surface 11 d. That is, the slant angle between the fittingsurface 30 a and the fitting surface 11 d after the radiator 10 and thefan shroud 30 are engaged becomes smaller than the set angle of 1.5°before the radiator 10 and the fan shroud 30 are engaged. Therefore,when the engagement hole portion 33 engages with the engagementprotruding portion 13, the fitting surface 30 a becomes approximatelyparallel to the fitting surface 11 d when being watched by human eyes.

In this embodiment, the fan shroud 30 is beforehand deformed by bendingto have approximately the large-angle V-shape in the fitting surface 30a. When the fan shroud 30 is engaged with the radiator 10, the fanshroud 30 is reformed and deflected, so that a counteractive force dueto the deflection is applied to the fan shroud 30 by the engagementprotruding portion 13. As a result, the fan shroud 30 is pressed to thetank body 11 a (i.e. side of radiator). Accordingly, a relative movementbetween the engagement protruding portion 13 and the engagement holeportion 33 can be restricted, even if a gap is formed therebetween whenbeing mounted.

When any one of the fitting surfaces 11 d, 30 a is not deformed (bent)beforehand as shown in FIG. 7, the counteractive force due to thedeflection is not applied when the radiator 10 and the shroud 30 areassembled. In this case, a relative movement occurs between the radiator10 and the fan shroud 30.

(Other Embodiment)

Although the present invention has been fully described in connectionwith the preferred embodiment thereof with reference to the accompanyingdrawings, it is to be noted that various changes and modifications willbecome apparent to those skilled in the art.

For example, in the above-described embodiment, the fitting surface 30 aof the fan shroud 30 is beforehand bent to be slant with respect to theflat fitting surface 11 d of the radiator 10. However, the presentinvention is not limited to this. The fitting surface 11 d, or both ofthe fitting surfaces 11 d and 30 a can be bent to be deformed.

According to the present invention, in order to restrict the relativemovement between the attachment member (shroud) and the heat exchanger(radiator), at least one of the fitting surfaces is deflected andreformed when being assembled. In the above-described embodiment, theshroud 30 is deflected and reformed in the assembly because the fittingsurface 30 a of the shroud 30 is deformed by bending before theassembly. Instead of the bending, other method can be also used suchthat the shroud 30 is deflected and reformed when being attached to theradiator 10.

Moreover, a set value of the slant angle between the fitting surface 30a and the fitting surfaces 11 d can be changed according to the size,material and rigidity of the fan shroud 30, and is not limited to theabove-described value.

Moreover, the shape of the engagement protruding portion 13, which isthe engagement portion in the present invention, is not limited to thatdescribed in the above-described embodiment.

Moreover, in the above-described embodiment, the engagement protrudingportion 13 is provided in the radiator 10, and the engagement holeportion 33 is provided in the shroud plate 30 to engage with theengagement protruding portion 13. However, the present invention is notlimited to this. For example, the engagement protruding portion 13 canbe also provided in the shroud plate 30, and the engagement hole portion33 can be also provided in the radiator 10.

Moreover, in the above-described embodiment, the attachment structure atthe lower attachment positions P4 and P5 is different from that at theupper attachment positions P1-P3. However, the attachment structure atall of the attachment positions can be the same as that at the upperattachment positions P1-P3.

Moreover, in the above-described embodiment, the shroud plate 30 isbeforehand bent to protrude to the side of the radiator 10 to haveapproximately the large-angle V-shape. However, the shroud plate 30 canbe also beforehand bent to protrude to a contrary side of the radiator10 to have approximately the large-angle V-shape. Furthermore, theshroud plate 30 can be also beforehand bent to have a wave shape.

Such changes and modifications are to be understood as being within thescope of the present invention as defined by the appended claims.

1. An attachment structure comprising: a heat exchanger forheat-exchanging between air and a fluid therein; a blower for blowingair to the heat exchanger; and an attachment member through which theblower is attached to the heat exchanger, wherein: one of the heatexchanger and the attachment member has at least one engagement portion,the engagement portion being detachably engaged by an elasticdeformation with a hole portion which is provided in other one of theheat exchanger and the attachment member; and at least one of the heatexchanger and the attachment member is deformed before the engagementportion is engaged with the hole portion, and is deflected and reformeddue to deformation when the engagement portion engages with the holeportion.
 2. An attachment structure comprising: a heat exchanger forheat-exchanging between air and a fluid therein; a blower for blowingair to the heat exchanger; and an attachment member through which theblower is attached to the heat exchanger, wherein: one of the heatexchanger and the attachment member has at least one engagement portion,the engagement portion being detachably engaged by an elasticdeformation with a hole portion which is provided in other one of theheat exchanger and the attachment member; the heat exchanger has afitting surface that is arranged opposite to a fitting surface of theattachment member when the engagement portion engages with the holeportion; and one of the fitting surfaces of the heat exchanger and theattachment member is bent to be tilted with respect to other one of thefitting surfaces before the engagement portion is engaged with the holeportion.
 3. The attachment structure according to claim 2, wherein whenthe engagement portion engages with the hole portion, at least one ofthe heat exchanger and the attachment member is deflected and reformedso that the fitting surfaces of the heat exchanger and the attachmentmember becomes approximately parallel to each other.
 4. The attachmentstructure according to claim 2, wherein: at least three the engagementportions are arranged in a line in an arrangement directionperpendicular to an air flowing direction of the heat exchanger; and theone of the fitting surfaces of the heat exchanger and the attachmentmember is bent to have a convex shape at an approximate middle area inthe arrangement direction before the engagement portion is engaged withthe hole portion.
 5. The attachment structure according to claim 4,wherein the one of the fitting surfaces of the heat exchanger and theattachment member is bent to have a wave shape before the engagementportion is engaged with the hole portion.
 6. The attachment structureaccording to claim 2, wherein the one of the fitting surfaces of theheat exchanger and the attachment member is on the attachment member. 7.The attachment structure according to claim 6, wherein the attachmentmember is made of resin.
 8. The attachment structure according to claim1, wherein: the engagement portion is provided in the heat exchanger;and the hole portion is provided in the attachment member.